Polycrystalline diamond bearings for rotating machinery with compliance

ABSTRACT

Methods and apparatus for providing compliance in bearings of rotating machinery are provided. The rotating machinery may include a drive shaft movably coupled within a bearing housing. Compliant bearing assemblies may interface engagement between the drive shaft and the bearing housing, including polycrystalline diamond bearing elements, each with an engagement surface, and an opposing engagement surface of a metal that contains diamond solvent-catalyst.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is Continuation-in-Part of U.S. patentapplication Ser. No. 16/049,608 (pending), entitled “PolycrystallineDiamond Radial Bearing”, filed on Jul. 30, 2018, which is incorporatedherein by reference in its entirety as if set out in full. The presentapplication claims the benefit of U.S. Provisional Patent ApplicationNo. 62/845,131 (pending), entitled “Threaded Positioning Mechanism”,filed on May 8, 2019, which is incorporated herein by reference in itsentirety as if set out in full.

FIELD

The present disclosure relates to polycrystalline diamond bearingelements having compliance for use in bearing applications in rotatingmachinery, including for use in industrial applications, such asturbines, pumps, compressors, generators, combustion engines, drillingtools, and other tools including downhole tools; to systems includingthe same; and to methods of making and using the same.

BACKGROUND

Radial bearings are used in tools, rotating machinery, and components tobear load. One application of radial bearings is in rotating machinery.In rotating machinery, typically one part, a rotor, is positionedrelative to and movably coupled with another part, a stator, such thatthe rotor moves (e.g., rotates) relative to the stator. Bearings can beused to facilitate the movable coupling between the rotor and stator.Such bearings can be positioned between the stator (e.g., a bearinghousing) and the rotor (e.g., a drive shaft) to allow rotation of therotor while the stator remains generally stationary. For example, suchrotating machinery may be positioned within a wellbore and may rotatewith a drill string.

In some applications, at low speeds, where the rotor (e.g., drive shaft)is moving at relatively low speeds and/or high loads relative to thestator (e.g., the bearing housing), the surfaces of the bearing elementsare directly in contact (i.e., boundary lubrication) with the opposingbearing surfaces, whereas, at high-speeds and/or low loads, where therotor is moving at relatively high speeds relative to the stator, afluid film may develop (i.e., hydrodynamic lubrication) between bearingelements and opposing bearing surfaces such that the surfaces of thebearing elements are not directly in contact with the opposing bearingsurfaces, but are engaged therewith through the fluid film. In suchapplications, the selective provision of a space between the bearingelements and opposing bearing surfaces when operating at high speedsprovides for the development of and maintenance of such fluid films whenneeded.

Also, when polycrystalline diamond bearing elements are used as radialbearings in rotating machinery, typically both the bearing engagementsurface and the opposing bearing engagement surface are composed ofpolycrystalline diamond. This is, at least in part, because thermallystable polycrystalline diamond (TSP), either supported or unsupported bytungsten carbide, and polycrystalline diamond compact (PDC or PCD) havebeen considered as contraindicated for use in the machining of diamondreactive materials, for example. Diamond reactive materials includemetals, metal alloys, composites, hardfacings, coatings, or platingsthat contain more than trace amounts of diamond catalyst or solventelements (also referred to as diamond solvent-catalysts or diamondcatalyst-solvents) including iron, cobalt, nickel, ruthenium, rhodium,palladium, chromium, manganese, copper, titanium, or tantalum. Further,this prior contraindication of the use of polycrystalline diamondextends to so called “superalloys”, including iron-based, cobalt-basedand nickel-based superalloys containing more than trace amounts ofdiamond catalyst or solvent elements. The surface speeds typically usedin machining of such materials typically ranges from about 0.2 m/s toabout 5 m/s when using sintered tungsten carbide cutting tools. Althoughthese surface speeds are not particularly high, the load and attendanttemperature generated, such as at a cutting tip, often exceeds thegraphitization temperature of diamond (i.e., about 700° C.), which can,in the presence of diamond catalyst or solvent elements, lead to rapidwear and failure of components. Without being bound by theory, thespecific failure mechanism is believed to result from the chemicalinteraction of the carbon bearing diamond with the carbon attractingmaterial that is being machined. An exemplary reference concerning thecontraindication of polycrystalline diamond for diamond catalyst orsolvent containing metal or alloy machining is U.S. Pat. No. 3,745,623.The contraindication of polycrystalline diamond for machining diamondcatalyst or diamond solvent containing materials has long caused theavoidance of the use of polycrystalline diamond in all contactingapplications with such materials.

BRIEF SUMMARY

Some embodiments of the present disclosure include a rotating machine.The rotating machine includes a stator, and a rotor movably coupled withthe stator. The rotor has a first opposing bearing engagement surfacethat comprises a material that contains from 2 to 100 weight percent ofa diamond solvent-catalyst, based on a total weight of the material. Acompliant bearing assembly is positioned between the rotor and thestator, and interfaces engagement between the rotor and the stator. Thecompliant bearing assembly includes a first bearing ring having a firstplurality of polycrystalline diamond bearing elements, each having afirst bearing engagement surface that is engaged with the first opposingengagement surface. The compliant bearing assembly includes a springcoupled with the first bearing ring and positioned on the first bearingring such that a distance between the first bearing engagement surfacesare the first opposing engagement surface is variable.

Another embodiment of the present disclosure includes a rotatingmachine. The rotating machine includes a stator and a rotor movablycoupled with the stator. The rotor has a first opposing bearingengagement surface that includes a material that contains from 2 to 100weight percent of a diamond solvent-catalyst, based on a total weight ofthe material. A bearing assembly is positioned between the rotor and thestator. The bearing assembly interfaces engagement between the rotor andthe stator. The bearing assembly includes a first bearing ring having afirst plurality of polycrystalline diamond bearing elements on an innersurface thereof, each with a first bearing engagement surface that isengaged with the first opposing engagement surface. The bearing assemblyincludes a second bearing ring having a second plurality ofpolycrystalline diamond bearing elements, each having a second bearingengagement surface. The second bearing engagement surfaces are engagedwith an outer surface of the first bearing ring. The first and secondbearing rings are arranged in a nested configuration between the statorand the rotor such that the second bearing ring is positioned betweenthe first bearing ring and the stator and the first bearing ring ispositioned between the second bearing ring and the rotor.

Another embodiment of the present disclosure includes a rotating machinethat includes a bearing housing having an outer surface and an innersurface, with the inner surface defining an annulus. A rotor is movablycoupled within the annulus of the bearing housing, The rotor has anopposing engagement surface that includes a material that contains from2 to 100 weight percent of a diamond solvent-catalyst, based on a totalweight of the material. A plurality of sockets are in the bearinghousing, and a plurality of polycrystalline diamond bearing elements arecoupled with the sockets. Each polycrystalline diamond bearing elementhas a bearing engagement surface that is engaged with the opposingengagement surface. The polycrystalline diamond bearing elements arecapable of tilting relative to the outer surface of the bearing housing.

Another embodiment of the present disclosure a method of bearing load ina rotating machine. The method includes providing a bearing housinghaving a first bearing ring including a first plurality ofpolycrystalline diamond bearing elements, each having a first bearingengagement surface. The bearing housing has an outer surface and aninner surface defining an annulus. The method includes providing a rotorthat is movably coupled with a stator, the rotor having an opposingengagement surface that includes a material that contains from 2 to 100weight percent of a diamond solvent-catalyst, based on a total weight ofthe material. The method includes positioning the bearing housingbetween the rotor and the stator to interface engagement between therotor and the stator. The first bearing engagement surfaces are engagedwith the opposing engagement surface. The method includes providing thepolycrystalline diamond bearing elements with compliance such that adistance between the first bearing engagement surfaces and the opposingengagement surface is variable in response to load and surface speed.

Another embodiment of the present disclosure a method of bearing load ina rotating machine. The method includes providing a first bearing ringhaving a first plurality of polycrystalline diamond bearing elements,each having a first bearing engagement surface. The method includesproviding a second bearing ring having a second plurality ofpolycrystalline diamond bearing elements, each having a second bearingengagement surface. The method includes providing a rotor that ismovably coupled with a stator, the rotor having an opposing engagementsurface that includes a material that contains from 2 to 100 weightpercent of a diamond solvent-catalyst, based on a total weight of thematerial. The method includes positioning the first bearing ring betweenthe rotor and the stator, with the first bearing engagement surfacesengaged with the opposing engagement surface. The method includespositioning the second bearing ring between the stator and the firstbearing ring, with the second bearing engagement surfaces engaged withan outer surface of the first bearing ring The first and second bearingrings are arranged in a nested configuration.

Another embodiment of the present disclosure a bearing assembly for usein rotating machines. The bearing assembly includes a first bearing ringhaving a first plurality of polycrystalline diamond bearing elements onan inner surface thereof, each having a first bearing engagement surfacethat is engaged with the first opposing engagement surface. The bearingassembly includes a spring coupled with the first bearing ring andpositioned on the first bearing ring such that a position of the firstbearing engagement surfaces is variable.

Another embodiment of the present disclosure a bearing assembly for usein rotating machinery. The bearing assembly includes a first bearingring including a first plurality of polycrystalline diamond bearingelements on an inner surface thereof. The bearing assembly has a secondbearing ring having a second plurality of polycrystalline diamondbearing elements having second bearing engagement surfaces, with thesecond bearing engagement surfaces engaged with an outer surface of thefirst bearing ring. The first and second bearing rings are arranged in anested configuration.

Another embodiment of the present disclosure a bearing assembly for usein rotating machines. The bearing assembly includes a bearing housinghaving an outer surface and an inner surface, the inner surface definingan annulus. A plurality of sockets are in the bearing housing, and aplurality of polycrystalline diamond bearing elements are coupled withthe sockets. Each polycrystalline diamond bearing element has a bearingengagement surface that is engaged with the opposing engagement surface.The polycrystalline diamond bearing elements are capable of tiltingrelative to the outer surface of the bearing housing.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and advantages of the systems,apparatus, and/or methods of the present disclosure may be understood inmore detail, a more particular description briefly summarized above maybe had by reference to the embodiments thereof which are illustrated inthe appended drawings that form a part of this specification. It is tobe noted, however, that the drawings illustrate only various exemplaryembodiments and are therefore not to be considered limiting of thedisclosed concepts as it may include other effective embodiments aswell.

FIG. 1 is a lateral, cross-sectional view of a portion of a bearingassembly for rotating machinery in accordance with some embodiments.

FIG. 2A is a detail view of the bearing assembly for rotating machineryof FIG. 1, with the polycrystalline diamond bearing elements in directcontact with a drive shaft and a bearing housing.

FIG. 2B is a detail view, similar to FIG. 2A, but with thepolycrystalline diamond bearing elements spaced-apart, and out of directcontact, from the drive shaft and the bearing housing.

FIG. 3 is a lateral, cross-sectional view of a portion of anotherbearing assembly for rotating machinery in accordance with someembodiments.

FIG. 4 is a lateral, cross-sectional view of a portion of anotherbearing assembly for rotating machinery in accordance with someembodiments.

FIG. 5A is a perspective view of a portion of another bearing assemblyfor rotating machinery in accordance with some embodiments.

FIG. 5B is a plan view of the bearing assembly of FIG. 5A.

FIG. 5C is a detail view of the bearing assembly of FIG. 5B.

FIG. 6A is a lateral, cross-sectional view of a portion of anotherbearing assembly for rotating machinery in accordance with someembodiments having nested bearing rings with flat bearing pads.

FIG. 6B is a detail view of the bearing assembly for rotating machineryof FIG. 6A.

FIG. 7A is a lateral, cross-sectional view of a portion of anotherbearing assembly for rotating machinery in accordance with someembodiments having nested bearing rings with arcuate bearing pads.

FIG. 7B is a detail view of the bearing assembly for rotating machineryof FIG. 7A.

FIG. 8A is a lateral, cross-sectional view of a portion of anotherbearing assembly for rotating machinery in accordance with someembodiments having arcuate bearing pads configured to tilt duringmovement of the drive shaft.

FIG. 8B is a view of the bearing assembly for rotating machinery of FIG.8A with the drive shaft not shown.

FIG. 8C is a view of the bearing assembly for rotating machinery of FIG.8A with the bearing housing not shown.

FIG. 8D is a detail view of a portion of the bearing assembly of FIG.8A.

FIG. 9A is a lateral, cross-sectional view of a portion of anotherbearing assembly for rotating machinery in accordance with someembodiments having arcuate bearing pads configured to tilt andcompliantly compress during movement of the drive shaft.

FIG. 9B is a view of the bearing assembly for rotating machinery of FIG.9A with the drive shaft not shown.

FIG. 9C is a view of the bearing assembly for rotating machinery of FIG.9A with the bearing housing not shown.

FIG. 9D is a view of the bearing assembly for rotating machinery of FIG.9A with a fluid film.

FIG. 10 is a schematic showing the stiffness and damping of bearingelements in accordance with some embodiments.

FIG. 11 is a portion of a drilling tool in accordance with someembodiments, including a drive shaft supported by multiple bearingassemblies.

FIG. 12 is an exemplary Stribeck curve.

Systems, apparatus, and methods according to present disclosure will nowbe described more fully with reference to the accompanying drawings,which illustrate various exemplary embodiments. Concepts according tothe present disclosure may, however, be embodied in many different formsand should not be construed as being limited by the illustratedembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough as well as complete and will fullyconvey the scope of the various concepts to those skilled in the art andthe best and preferred modes of practice.

DETAILED DESCRIPTION

Certain embodiments of the present disclosure include methods andapparatus for providing compliance to polycrystalline diamond bearingelements. The present disclosure includes polycrystalline diamondbearing elements, bearing rings, and bearing mounts that have or providecompliance; systems and rotating machinery and components thereof havingsuch polycrystalline diamond bearings, bearing rings, and bearingmounts; and methods of making and using the same. The bearing assembliesdisclosed herein may be used in rotating machinery (includingturbomachinery), such as motors and turbines. When used in motors, themotors may be, but are not limited to, drilling motors for downholedrilling, including directional drilling, such as mud motors. Thebearing assemblies disclosed herein may be used in apparatus including,but not limited to, gearboxes, turbines, pumps, compressors, miningequipment, drilling equipment, construction equipment, combustionengines, windmills, automotive parts, and aircraft parts.

Certain embodiments include drive shafts having polycrystalline diamondbearings (e.g., radial bearings) thereon. For convenience, certain partsof the following descriptions disclose a stator component and a rotorcomponent. However, it would be understood by one skilled in thetechnology disclosed herein may be applied to various parts that aremovably engaged, such as to a drive shaft movably coupled within ahousing. Also, for convenience, certain parts of the followingdescriptions present an outer stator component and an inner rotorcomponent. However, it would be understood by one skilled in the artthat the inner component may be held static and the outer component maybe rotated. Additionally, it would be understood by one skilled in theart that, although the descriptions of the disclosure are directed torotor and stator configurations, the technology disclosed herein is notlimited to such applications and may be applied in various otherapplications including discrete bearings with an inner and outer racewhere the outer and inner races both rotate or where either one or theother of the outer and inner races is held stationary. While thedisclosure describes methods, systems, and apparatus for providingcompliance in radial bearings, such as in rotating machinery, themethods, systems, and apparatus for providing compliance disclosedherein are not limited to use in radial bearings, and may include thrustbearings, radial bearings, combined thrust/radial bearings, or otherbearing apparatuses including bearing surfaces that move in relation toone another. For example, the methods, systems, and apparatus forproviding compliance to polycrystalline diamond bearing elementsdisclosed herein may be used in: the drilling tools of U.S. patentapplication Ser. No. 16/561,335 (the '335 Application); the radialbearings disclosed in U.S. patent application Ser. No. 16/049,608 (the'608 Application); the thrust bearings disclosed in U.S. patentapplication Ser. No. 16/049,617 (the '617 Application); the bearings ofthe roller ball assembly disclosed in U.S. patent application Ser. No.16/049,631 (the '631 Application); and the bearings of the tubularassemblies disclosed in U.S. patent application Ser. No. 16/529,310 (the'310 Application). Each of the '617 Application, the '631 Application,and the '310 Application are incorporated herein by reference in theirentireties as if set out in full. Furthermore, the methods, systems, andapparatus for providing compliance to polycrystalline diamond bearingelements disclosed herein may be used in the bearing engagementsdisclosed in U.S. patent application Ser. No. 16/425,758 (the '758Application), where the opposing bearing surface that engages with thebearing surface of the polycrystalline diamond bearing element is atreated surface. The entirety of the '758 Application is incorporatedherein by reference in its entirety as if set out in full. Furthermore,while the methods, systems, and apparatus for providing compliance topolycrystalline diamond bearing elements disclosed herein are describedin reference to downhole rotating machinery, the methods, systems, andapparatus disclosed herein are not limited to such applications and maybe used in other oil and gas components (e.g., surface components) orused in applications other than oil and gas applications.

Definitions, Examples, and Standards

Diamond Reactive Materials—As used herein, a “diamond reactive material”is a material that contains more than trace amounts of diamond catalystor diamond solvent, which are also referred to as “diamondcatalyst-solvent,”, “catalyst-solvent,” “diamond solvent-catalyst,” or“solvent-catalyst.” Some examples of known solvent-catalysts aredisclosed in: U.S. Pat. Nos. 3,745,623; 7,198,043; 8,627,904; 5,385,715;8,485,284; 6,814,775; 5,271,749; 5,948,541; 4,906,528; 7,737,377;5,011,515; 3,650,714; 2,947,609; and 8,764,295. As used herein, adiamond reactive material that contains more than “trace amounts” ofdiamond catalyst or diamond solvent, is a material that contains atleast 2 percent by weight (wt. %) diamond catalyst or diamond solvent.In some aspects, the diamond reactive materials disclosed herein containfrom 2 to 100 wt. %, or from 5 to 95 wt. %, or from 10 to 90 wt. %, orfrom 15 to 85 wt. %, or from 20 to 80 wt. %, or from 25 to 75 wt. %, orfrom 25 to 70 wt. %, or from 30 to 65 wt. %, or from 35 to 60 wt. %, orfrom 40 to 55 wt. %, or from 45 to 50 wt. % of diamond catalyst ordiamond solvent. As would be understood by one skilled in the art,diamond solvent-catalysts are chemical elements, compounds, or materials(e.g., metals) that are capable of reacting with polycrystalline diamond(e.g., catalyzing and/or solubilizing), resulting in the graphitizationof the polycrystalline diamond, such as under load and at a temperatureat or exceeding the graphitization temperature of diamond (i.e., about700° C.). Thus, diamond reactive materials include materials that, underload and at a temperature at or exceeding the graphitization temperatureof diamond, can lead to wear, sometimes rapid wear, and failure ofcomponents formed of or including polycrystalline diamond, such asdiamond tipped tools. Diamond reactive materials include, but are notlimited to, metals, metal alloys, and composite materials that containmore than trace amounts of diamond solvent-catalysts. In some aspects,the diamond reactive materials are in the form of hardfacings, coatings,or platings. Some exemplary diamond solvent-catalysts include iron,cobalt, nickel, ruthenium, rhodium, palladium, chromium, manganese,copper, titanium, tantalum, and alloys thereof. Thus, a diamond reactivematerial may be a material that includes more than trace amounts ofiron, cobalt, nickel, ruthenium, rhodium, palladium, chromium,manganese, copper, titanium, tantalum, or alloys thereof. One exemplarydiamond reactive material is steel. In some aspects, the diamondreactive material is a superalloy including, but not limited to, aniron-based superalloy, a cobalt-based superalloy, or a nickel-basedsuperalloy. In certain aspects, the diamond reactive material is notand/or does not include (i.e., specifically excludes) so called“superhard materials.” As would be understood by one skilled in the art,“superhard materials” are a category of materials defined by thehardness of the material, which may be determined in accordance with theBrinell, Rockwell, Knoop and/or Vickers scales. For example, superhardmaterials include materials with a hardness value exceeding 40gigapascals (GPa) when measured by the Vickers hardness test. As usedherein, “superhard materials” are materials that are at least as hard astungsten carbide, including tungsten carbide tiles and cemented tungstencarbide, such as is determined in accordance with one of these hardnessscales. One skilled in the art would understand that a Brinell scaletest may be performed, for example, in accordance with ASTM E10-18; theVickers hardness test may be performed, for example, in accordance withASTM E92-17; the Rockwell hardness test may be performed, for example,in accordance with ASTM E18; and the Knoop hardness test may beperformed, for example, in accordance with ASTM E384-17. The “superhardmaterials” disclosed herein include, but are not limited to, tungstencarbide (e.g., tile or cemented), infiltrated tungsten carbide matrix,silicon carbide, silicon nitride, cubic boron nitride, andpolycrystalline diamond. Thus, in some aspects, the “diamond reactivematerial” is partially or entirely composed of material(s) (e.g., metal,metal alloy, composite) that is softer (less hard) than superhardmaterials, such as less hard than tungsten carbide (e.g., tile orcemented), as determined in accordance with one of these hardness tests,such as the Brinell scale.

Interfacing Polycrystalline Diamond with Diamond Reactive Materials—Insome aspects, the present disclosure provides for interfacing theengagement between a rotor and stator with a polycrystalline diamondbearing element in contact with a diamond reactive material. Forexample, the polycrystalline diamond bearing element may be positionedand arranged on the stator for sliding contact with the rotor, where therotor is formed of or includes at least some diamond reactive material.Alternatively, the polycrystalline diamond bearing element may bepositioned and arranged on the rotor for sliding contact with thestator, where the stator is formed of or includes at least some diamondreactive material. Alternatively, the polycrystalline diamond bearingelement may be positioned and arranged on a bearing ring between therotor and the stator for sliding contact with the rotor and stator,where the rotor and stator are formed of or include at least somediamond reactive material. The polycrystalline diamond bearing elementmay have an engagement surface for engagement with an opposingengagement surface of the diamond reactive material. As used herein,“engagement surface” refers to the surface of a material or component(e.g., polycrystalline diamond or diamond reactive materials) that ispositioned and arranged within a bearing assembly such that, inoperation of the bearing assembly, the engagement surface interfaces thecontact between two components (e.g., between the stator and the rotor).The “engagement surface” may also be referred to herein as the “bearingsurface.”

Lapped or Polished—In certain applications, the polycrystalline diamondbearing element, or at least the engagement surface thereof, is lappedor polished, optionally highly lapped or highly polished. Althoughhighly polished polycrystalline diamond bearing elements are used in atleast some applications, the scope of this disclosure is not limited tohighly polished polycrystalline diamond bearing elements and includespolycrystalline diamond bearing elements that are highly lapped orpolished. As used herein, a surface is defined as “highly lapped” if thesurface has a surface finish of 20 μin or about 20 μin, such as asurface finish ranging from about 18 to about 22 μin. As used herein, asurface is defined as “polished” if the surface has a surface finish ofless than about 10 μin, or of from about 2 to about 10 μin. As usedherein, a surface is defined as “highly polished” if the surface has asurface finish of less than about 2 μin, or from about 0.51 μin to lessthan about 2 μin. In some aspects, the polycrystalline diamondengagement surfaces disclosed herein have a surface finish ranging from0.5 μin to 40 μin, or from 2 μin to 30 μin, or from 5 μin to 20 μin, orfrom 8 μin to 15 μin, or less than 20 μin, or less than 10 μin, or lessthan 2 μin, or any range therebetween. Without being bound by theory, itis believed that polycrystalline diamond that has been polished to asurface finish of 0.5 μin has a coefficient of friction that is abouthalf of standard lapped polycrystalline diamond with a surface finish of20-40 μin. U.S. Pat. Nos. 5,447,208 and 5,653,300 to Lund et al., theentireties of which are incorporated herein by reference, providedisclosure relevant to polishing of polycrystalline diamond. As would beunderstood by one skilled in the art, surface finish, also referred toas surface texture or surface topography, is a characteristic of asurface as defined by lay, surface roughness, and waviness. Surfacefinish may be determined in accordance with ASME B46.1-2009. Surfacefinish may be measured with a profilometer, laser microscope, or withAtomic Force Microscopy, for example.

Fluid Film Bearing Operation and Direct Sliding Contact Operation

In some embodiments, the bearing assemblies disclosed herein are capableof operating in at least two states, including a first state in whichthe bearing surfaces of the bearing assembly are in direct slidingcontact with one another and little to no fluid film is present betweenthe bearing surfaces of the bearing assembly; and a second state inwhich a fluid film is positioned between the bearing surfaces of thebearing assembly and the bearing surfaces of the bearing assembly arenot in direct contact with one another. As would be understood by oneskilled in the art, a “fluid film bearing” (also referred to as a “fluidbearing”) is a bearing in which load is supported by a layer of moving,pressurized liquid or gas that is positioned between the bearingsurfaces of the bearing assembly. When a fluid film bearing issufficiently present, there is no contact between the opposing bearingsurfaces, and there is no contact between the moving parts (i.e.,between the stator and rotor).

At some operational conditions, a fluid film bearing is formed betweenthe bearing surfaces of the components of the rotating machine. Oneskilled in the art would understand that the particular operationalconditions under which a fluid film bearing is formed will varydepending upon the particular rotating machine and the particularapplication thereof. Parameters that affect the development of a fluidfilm bearing include, but are not limited to, surface speed and bearingload. As used herein, the “surface speed” is the relative velocitybetween the rotor and the stator of the rotating machine. As usedherein, the “bearing load” is the load on the bearing assembly of therotating machine. The rotating machines disclosed herein may developfluid film bearings between the bearing surfaces thereof under“high-load/low speed” operational conditions, and under “low-load/highspeed” operational conditions. For example, at a relatively low bearingload of “Y” in a particular bearing assembly of a particular rotatingmachine, a fluid film bearing may develop only at or above a relativelyhigh surface speed of “Z”. Whereas, for the same bearing assembly andsame rotating machine, a fluid film bearing may develop at a relativelyhigh load of “V” even at a relatively low surface speed of “Z⁻”. Inthese examples, Y⁺ is greater than Y, and Z⁻ is less than Z.

One exemplary operational condition in which a rotating machine mightoperate in a state in which no fluid film is between the bearingsurfaces of the bearing assembly such that the bearing surfaces are indirect sliding contact with one another is during “start-up” of arotating machine. As used herein, “start-up” refers to an operationalstate of a rotating machine wherein movement (e.g., rotation) of onecomponent (e.g., a drive shaft or other rotor) in the rotating machineis initiated, and including subsequent acceleration and movement of thatone component under load conditions and at a surface speed relative tothe other component where there is no fluid film bearing developedbetween the bearing surfaces of the components of the rotating machine.Another exemplary operational condition in which a rotating machinemight operate in a state in which no fluid film is between the bearingsurfaces of the bearing assembly such that the bearing surfaces are indirect sliding contact with one another is during “shut-down”. As usedherein, “shut-down” refers to an operational state of a rotating machinewherein the rotating machine was previously operating with a fluid filmbearing but has transitioned to operating without a fluid film bearing,with the bearing surfaces in direct sliding contact. For example, at aset load, the surface speed may be reduced from a surface speed whereina fluid film is developed between the bearing surfaces to a lowersurface speed wherein no fluid film is developed; or, alternatively, ata set surface speed, the load on the bearing may be reduced from a loadwherein a fluid film is developed between the bearing surfaces to alower load wherein no fluid film is developed. For example, “start-up”may include initiation of and acceleration of movement of the rotatingmachine from a prior state of non-movement up to a state where a fluidfilm is developed, and “shut-down” may include the deceleration of themovement of the rotation machine from a state where a fluid film isdeveloped to a state where no fluid film is developed and the continueddeceleration of the rotating machine until the movement of the rotatingmachine has ceased.

As used herein “engaged” or “engage”, in reference to surfaces, refersto surfaces that are in contact with one another both directly (i.e.,direct contact) and surfaces that are coupled with a fluid film betweenthe surfaces where the surfaces are not in direct contact. As usedherein, “direct contact”, in reference to surfaces, refers to surfacesthat are physically touching one another without any intermediate mediuminterfacing the contact between the surfaces (e.g., without a fluid filminterfacing the contact).

Compliance—As used herein, “compliance,” in relation to a bearingelement, refers to the ability of the bearing element to elasticallymove in response to load. For example, the bearing element may have amagnitude of elastic variation in the orientation, position, or both theorientation and position in response to load. For example, the bearingelement may be mounted in a manner that allows for variation in theorientation, position, or orientation and position of the bearingengagement surface of the bearing element. Such variation may bereferred herein as “compliance” or “compliant,” i.e., the ability of themounting structure of the bearing element to elastically deform orotherwise allow or accommodate variations in orientation and/or positionwhen a force is applied to the bearing engagement surface of the bearingelement. The compliance of the bearing elements disclosed herein mayprovide for the development of fluid films between the bearingengagement surface and an opposing engagement surface. The compliance ofthe bearing elements disclosed herein may provide the bearing elementswith the ability to adjust in response to loads, including non-uniformloads and misalignment between moving parts (e.g., rotors and stators).

While the bearing assemblies are described in reference to specificembodiment herein, the bearing assemblies disclosed herein are notlimited to the specific applications described, and may be used inrotating machinery where fluid film lubrication and/or tilting bearingpads facilitate the development of a fluid film and where compliancefacilitates the ability to reduce and vibration in the rotatingmachinery.

While the present disclosure describes compliant bearing assembliesprovided in bearing rings that are positioned between a rotor andstator, the compliant bearings may be provided directly on the rotor,the stator, or combinations thereof. In some embodiments, where anengagement surface is slidingly engaged with an opposing engagementsurface, one or both of the engagement surface and opposing engagementsurface is provided with compliant bearings in accordance with thepresent disclosure.

Bearing Assembly with Compliant Bearing Rings and Damping

Throughout the present disclosure, like references numerals are used torefer to like elements. For example, in FIG. 1 a “drive shaft” isidentified as numeral “106”, whereas, in FIG. 3 a “drive shaft” isidentified as numeral “306”. With reference to FIG. 1, rotating machine1000 is depicted. Rotating machine 1000 may be a downhole tool, such asa downhole motor or tool, for use in downhole oil and gas exploration,drilling, and production operations. For example, and withoutlimitation, rotating machine 1000 may be a mud motor or drilling motoror a pump. Rotating machine 1000 includes a stator component and a rotorcomponent. In the embodiment of FIG. 1, the stator component is outerhousing 100. Outer housing 100 may be a portion of a drill string, suchas a bearing housing or motor housing, or another component of a drillstring. Outer housing 100 includes outer surface 102 and inner surface104.

In the embodiment of FIG. 1, the rotor component is drive shaft 106.Drive shaft 106 is positioned within the annulus defined by the innersurface 104 of outer housing 100. While drive shaft 106 is shown as asolid structure, the drive shafts and other rotors disclosed herein arenot limited to being solid structures, and may be hollow or at leastpartially hollow structures. Drive shaft 106 includes outer surface 108.

Rotating machine 1000 includes bearing assembly 110 interfacingengagement between drive shaft 106 and outer housing 100. Bearingassembly 110 includes outer bearing ring 112 and inner bearing ring 114.Outer bearing ring 112 includes outer surface 116 and inner surface 118.A plurality of polycrystalline diamond bearing elements 120 are coupledwith outer bearing ring 112. Each polycrystalline diamond bearingelement 120 includes a bearing engagement surface 122. Eachpolycrystalline diamond bearing element 120 on outer bearing ring 112extends from outer surface 116 of outer bearing ring 112 and towardsinner surface 104 of outer housing 100. Inner bearing ring 114 includesouter surface 124 and inner surface 126. A plurality of polycrystallinediamond bearing elements 120 are coupled with inner bearing ring 114.Each polycrystalline diamond bearing element 120 includes a bearingengagement surface 122. Each polycrystalline diamond bearing element 120on inner bearing ring 114 extends from inner surface 126 of innerbearing ring 114 and towards outer surface 108 of drive shaft 106. Thus,one plurality of polycrystalline diamond bearing elements 120 may becoupled with and extend, intermittently, about the entire innercircumference of inner bearing ring 114, and another plurality ofpolycrystalline diamond bearing elements 120 may be coupled with andextend, intermittently, about the entire outer circumference of outerbearing ring 112.

Inner surface 118 of outer bearing ring 112 has a surface that is shapedto mate with the shape of outer surface 124 of inner bearing ring 114.For example, as shown in FIG. 1, surface 118 is shaped to define gearteeth 128 and surface 124 is shaped to define gear teach 130, and outerbearing ring 112 and inner bearing ring 114 are coupled such that thegear teeth 128 and 130 mesh with one another, allowing for the transferof torque from one bearing ring to the other. The coupling of the innerand outer bearing rings disclosed herein is not limited to the use ofgear-teeth-shaped surfaces, as is shown in FIG. 1, and may use othercoupling mechanisms for the transfer of torque from one of the bearingrings to the other.

Bearing assembly 110 includes one or more biasing or compliancemechanisms, here shown as springs 132 coupled with surfaces 124 and 118.Springs 132 bias bearing rings 112 and 114 into a position where bearingrings 112 and 114 are spaced-apart from one another, such that cavity134 is formed between bearing rings 112 and 114. While shown as springs,the biasing mechanisms (also referred to as a “compliance members”)disclosed herein are not limited to springs and may be or include otherstructures capable biasing the bearing rings into a spaced-apartrelationship. For example, the springs disclosed herein may be replacedwith an elastic material, such as rubber that compresses when undersufficient forces (e.g., load, surface speed, fluid pressure) andelastically decompresses when conditions are no longer sufficient tocompress the rubber. In some embodiments, the spring disclosed hereinmay be replaced with a solid elastically compressible material. Forexample, under certain operating conditions (e.g., certain loads andsurface speeds), relatively hard materials, such as steel, can exhibitelastic compressibility. In some embodiments, the compliance member is aspring washer, such as a wave spring washer, a curved spring washer, ora Belleville spring washer. The springs disclosed herein may bepre-loaded to a desired stiffness, depending on the particularapplication. Springs 132 may bias bearing surfaces 122 ofpolycrystalline diamond bearing elements 120 on outer bearing ring 112into direct contact with inner surface 104 of outer housing 100. Springs132 may bias bearing surfaces 122 of polycrystalline diamond bearingelements 120 on inner bearing ring 114 into direct contact with outerssurface 108 of drive shaft 106. Rotating machine 1000 may include aplurality of springs 132 that are coupled between the inner and outerbearing rings, and extend, intermittently, about the entire innercircumference of outer bearing ring 112 and about the entire outercircumference of inner bearing ring 114.

In some embodiments, one or more of outer housing 100, drive shaft 106,outer bearing ring 112, and inner bearing ring 114 are or include ametal or metal alloy that contains at least 2 wt. % of a diamondsolvent-catalyst, such as iron, cobalt, nickel, ruthenium, rhodium,palladium, chromium, manganese, copper, titanium, tantalum, or alloysthereof. In some embodiments, one or more of outer housing 100, driveshaft 106, outer bearing ring 112, and inner bearing ring 114 are orinclude a metal or metal alloy that contains from 2 to 100 wt. %, orfrom 5 to 95 wt. %, or from 10 to 90 wt. %, or from 15 to 85 wt. %, orfrom 20 to 80 wt. %, or from 25 to 75 wt. %, or from 25 to 70 wt. %, orfrom 30 to 65 wt. %, or from 35 to 60 wt. %, or from 40 to 55 wt. %, orfrom 45 to 50 wt. % of diamond solvent-catalyst, such as iron, cobalt,nickel, ruthenium, rhodium, palladium, chromium, manganese, copper,titanium, tantalum, or alloys thereof. As such, in some embodiments oneor more of surfaces 104, 116, 126, and 108 contain at least 2 wt. %, orfrom 2 to 100 wt. %, or from 5 to 95 wt. %, or from 10 to 90 wt. %, orfrom 15 to 85 wt. %, or from 20 to 80 wt. %, or from 25 to 75 wt. %, orfrom 25 to 70 wt. %, or from 30 to 65 wt. %, or from 35 to 60 wt. %, orfrom 40 to 55 wt. %, or from 45 to 50 wt. % of diamond solvent-catalyst,such as iron, cobalt, nickel, ruthenium, rhodium, palladium, chromium,manganese, copper, titanium, tantalum, or alloys thereof.

In operation, drive shaft 106 rotates as indicated via rotation arc 136.At low rotation speeds, such as at start-up when drive shaft 106 firstbegins to rotate after being static, bearing surfaces 122 ofpolycrystalline diamond bearing elements 120 on inner bearing ring 114are in direct contact with outer surface 108. With bearing surfaces 122in direct contact with outer surface 108, rotation of drive shaft 106transfers torque to the engaged polycrystalline diamond bearing elements120; thereby, causing inner bearing ring 114 to also rotate. With innerbearing ring 114 coupled with outer bearing ring 112 via meshing of gearteeth 128 and 130, inner bearing ring 114 transfers torque to outerbearing ring 112, such that outer bearing ring 112 also rotates. At lowrotation speeds, such as at start-up when drive shaft 106 first beginsto rotate after being static, bearing surfaces 122 of polycrystallinediamond bearing elements 120 on outer bearing ring 112 are in directcontact with inner surface 104.

As shown in FIG. 2B, in some applications, after start-up and whenrotation speed of drive shaft 106 has increased, a fluid film developsin space 138 between outer housing 100 and outer bearing ring 112, andin space 140 between inner bearing ring 114 and drive shaft 106. Inparticular, the fluid film develops between the bearing surfaces 122 andthe inner surface 104, as well as between the bearing surfaces 122 andthe outer surface 108. For example, and without limitation, in someapplications, a lubricant, drilling fluid, drilling mud, or anotherfluid is pumped between the drive shaft 106 and outer housing 100, suchthat the fluid resides within spaces 138 and 140. In some suchapplications, rotating machine 1000 reaches operating conditionssufficient to cause the fluid pressure of the fluid to overcome the biasof springs 132, such that the fluid film is formed in spaces 138 and140, such that bearing surfaces 122 of polycrystalline diamond bearingelements 120 on outer bearing ring 112 are forced out of direct contactwith inner surface 104 of outer housing 100, and such that bearingsurfaces 122 of polycrystalline diamond bearing elements 120 on innerbearing ring 114 are forced out of direct contact with outers surface108 of drive shaft 106. Factors that may contribute to operatingconductions sufficient for formation of the fluid film may include, butare not limited to, the operating temperature of rotating machine 1000,the rotation speed of drive shaft 106, properties of the lubricant,bearing loads on rotating machine 1000, and the flow rate of the fluidbeing pumped through rotating machine 1000. After start-up of rotatingmachine 1000, and before shut-down of rotating machine 1000, drive shaft106 and bearing assembly 110 may rotate at the same or substantially thesame rate.

During shut down, as the rotation of drive shaft 106 slows down to lowerrotation speeds, when the fluid pressure of the fluid no longerovercomes the bias of springs 132, springs 132 once again bias bearingsurfaces 122 of polycrystalline diamond bearing elements 120 on innerbearing ring 114 into direct contact with outer surface 108, and biasbearing surfaces 122 of polycrystalline diamond bearing elements 120 onouter bearing ring 112 into direct contact with inner surface 104. Assuch, rotating machine 1000 may develop a fluid film bearing betweenstart-up and shut-down of rotating machine 1000, and may operate withouta fluid film bearing during at least a portion of start-up and shut-downof rotating machine 1000. When operating without a fluid film, bearingsurfaces 122 of polycrystalline diamond bearing elements 120 on innerbearing ring 114 are in direct and sliding contact with outer surface108 and slide there-along as drive shaft 106 rotates, and bearingsurfaces 122 of polycrystalline diamond bearing elements 120 on outerbearing ring 112 are in direct and sliding contact with inner surface104 and slide there-along as bearing assembly 110 rotates. Whenoperating with a fluid film, the fluid film may be of sufficientpressure to continuously or substantially continuously maintain thebearing surfaces 122 out of direct contact with outer surface 108 andinner surface 104. The presence of a fluid film may reduce theoccurrence of wear on outer surface 108 and inner surface 104.

In operation, bearing assembly 110 is positioned between drive shaft 106and outer housing 110 to limit lateral and/or axial movement of driveshaft 106, while allowing for free sliding rotation of drive shaft 106during operation rotating machine 1000.

FIGS. 2A and 2B depict rotating machine 1000 before and after thedevelopment of a fluid film 142, respectively. As shown, when the fluidpressure of fluid 142 is sufficient to overcome the bias of springs 132,springs 132 compress such that outer bearing ring 112 and inner bearingring 114 move toward one another, such that cavity 134 is reduced oreliminated, space 138 is formed between outer housing 100 and outerbearing ring 112, and space 140 is formed between shaft 106 and innerbearing housing 114. Thus, the spaces 138 and 140 provide for fluid film142 therein, such that the bearing between shaft 106 and outer housing100 is at least partially and at least temporarily a fluid film bearing.

FIG. 3 depicts another embodiment of a rotating machine, rotatingmachine 3000. Rotating machine 3000 is substantially identical torotating machine 1000, with the exception that outer bearing ring 312and inner bearing ring 314 are both segmented rings. As shown, innerbearing ring 314 includes three segments, 314 a, 314 b, and 314 c, andouter bearing ring 312 includes three segments, 312 a, 312 b, and 312 c.

While FIGS. 1-3 depict embodiments with multiple springs positioned toprovide compliance between the inner and outer bearing rings, thepresent disclosure is not limited to such an embodiment, and may includeonly a single spring coupled between the inner and outer bearing rings.For example, and without limitation, a single coil spring, the same orsimilar to an energizer spring seal, may be positioned between the innerand outer bearing rings to provide elastic compliance thereto.

FIG. 4 depicts another embodiment of a rotating machine, rotatingmachine 4000. Rotating machine 4000 is substantially identical torotating machine 1000, with the exception of the shapes of inner surface418 of outer bearing ring 412 and outer surface 424 of inner bearingring 414. In FIG. 4, surfaces 418 and 424 are both shaped to definepeaks 427 and valleys 429, with outer bearing ring 412 and inner bearingring 414 are coupled such that the peaks 427 and valleys 429 of outerbearing ring 412 mesh with peaks 427 and valleys 429 of inner bearingring 414, allowing for the transfer of torque from one bearing ring tothe other.

FIGS. 5A-5C depict another embodiment of a bearing assembly for use inrotating machinery, bearing assembly 510. In bearing assembly 510,rather than having a spring coupled between two separate inner and outerbearing rings, compliance and tilting is provided via machined cavitieswithin a single bearing ring. The bearing ring can be machined to haveone or more internal cavities configured to provide compliance and/ortilting capabilities to the bearing ring. Bearing assembly 510 includesbearing ring body 511, which is machined (e.g., via electrical dischargemachining (EDM)) to have outer bearing section 512 (also referred to asouter flange) and inner bearing section 514 (also referred to as innerflange). Some embodiments of the bearing assemblies disclosed herein maybe machined and provided with the cavities in accordance with thedisclosure of U.S. Pat. No. 5,489,155, the entirety of which isincorporated herein by reference. The machining of bearing ring body 511defines cavities 513 that are positioned between outer bearing section512 and inner bearing section 514, and arranged such that outer bearingsection 512 and inner bearing section 514 are compressible toward oneanother. Cavities 513 provide a gap within which fluid may enter toprovide a fluid film bearing, such that cavities 513 provide a squeezefilm area (also referred to as squeeze film bearing dampers and squeezefilm dampers). Thus, in operation, cavities 513 are lubricated viafluid, providing viscous damping in bearing assembly 510. Cavities 513may provide structural isolation between the rotor and stator of anassociated rotating machine, reduce the amplitudes of rotor response toimbalance, and suppress rotor dynamic instability. The machining ofbearing ring body 511 also includes machining cavities that defineintegral springs within bearing ring body 511, here shown as S-typesprings 515 (i.e., S-shaped cavities). When fluid pressure exceeds theforce of S-type springs 515, outer bearing section 512 and inner bearingsection 514 are compressed toward one another.

Also shown is the holes 516, which are residual of the EDM process, andwithin which fluid may enter during operations. The machining of bearingring body 511 also includes machining cavities 517 that define tillableand/or pivotable bearing pads 519 on inner surface 559 of inner bearingsection 514. As shown in the detail view of FIG. 5C, two cavities 517define bearing pad 519. The two cavities 517 that define bearing pad 519define a first section 525, proximate inner surface 559, where the twocavities 517 are spaced apart from one another to define bearing pad519. The two cavities 517 that define bearing pad 519 also define asecond section 523, positioned further from inner surface 559 than firstsection 525, where the two cavities 517 are spaced more closely togetherthan in first section 525 to define fulcrum 527. In operation, fluidenters cavities 517, and fulcrum 527 allows bearing pad 519 to tiltand/or pivot in response to loads thereon. Positioned on or integralwith each bearing pad 519 is polycrystalline bearing compact 520,defining bearing surface 522.

The cavities providing within bearing ring body 511 are not limited tothe particular arrangement shown in FIGS. 5A-5C, and may be arranged inother manners that provide compliance to bearing assembly 510. Bearingassembly 510 defines annulus 539 within which a drive shaft or othermoving part may be positioned for engagement with engagement surfaces522.

Nested Rings

In some embodiments, the bearing assemblies disclosed herein includemultiple bearing rings that are nested together. With references toFIGS. 6A and 6B, rotating machine 6000 is depicted. Rotating machine6000 includes drive shaft 606 positioned within outer housing 600 (i.e.,stator). Between drive shaft 606 and outer housing 600, bearing assembly610 is positioned to interface the engagement of drive shaft 606 andouter housing 600. Bearing assembly 610 includes outer bearing ring 612and inner bearing ring 614. Coupled to or integral with outer bearingring 612 and inner bearing ring 614 are a plurality of polycrystallinediamond bearing elements 620. Each polycrystalline diamond bearingelements 620 of inner bearing ring 614 includes support member 617,which may be tungsten carbide, and polycrystalline diamond bearingelement 619 coupled thereon and defining bearing engagement surface 622.

The polycrystalline diamond bearing elements 620 of inner bearing ring614 define flat bearing engagement surfaces 622 that are arrangedrelative to drive shaft 606 such that a portion of bearing engagementsurfaces 622 are engageable with outer surface 608 of drive shaft 606,and another portion of bearing engagement surfaces 621 is spaced-apartfrom drive shaft 606. As such, less than an entirety of bearingengagement surfaces 622 are engaged with drive shaft 606, even at lowspeeds during start-up and shut-down. Also, inner surface 626 of innerbearing ring 614 is maintained in a spaced-apart relationship from outersurface 608 of drive shaft 606.

The polycrystalline diamond bearing elements 620 of outer bearing ring612 define flat bearing engagement surfaces 622 that are arrangedrelative to drive shaft inner bearing ring 614 such that a portion ofbearing engagement surfaces 622 are engageable with outer surface 624 ofinner bearing ring 614, and another portion of bearing engagementsurfaces 621 is spaced-apart from inner bearing ring 614. As such, lessthan an entirety of bearing engagement surfaces 622 are engaged withinner bearing ring 614, even at low speeds during start-up andshut-down. Also, inner surface 618 of outer bearing ring 612 ismaintained in a spaced-apart relationship from outer surface 624 ofinner bearing ring 612.

In operation, drive shaft 606 rotates. Bearing surfaces 622 are indirect contact with outer surface 608, such that rotation of drive shaft606 transfers torque to the engaged polycrystalline diamond bearingelements 620; thereby, causing inner bearing ring 614 to also rotate.Outer bearing ring 612 is coupled with outer housing 600, such thatouter bearing ring 612 remains static relative to outer housing 6000.

In some embodiments, outer bearing ring 612 of bearing assembly 610 caninclude a material that is elastically compressible under bearing loads.In FIG. 6B, outer bearing ring 612 has a geometry configured to providecompliance to bearing assembly 610. In particular, outer bearing ring612 is machined to have cavity 617, which defines spring 615. Inoperation, under sufficient loads and/or surface speeds, spring 615compresses, at least partially closing cavity 617. In some embodiments,bearing assembly 610 includes a squeeze film damper. In operation,bearing assembly 610 may reduce the relative sliding speed of engagedsurfaces of rotating machine 6000, such as by reducing the relativesliding speed between PDCs 620 and the engagement surfaces of therotating machine 6000 relative to an otherwise identical bearingassembly that includes only a single bearing ring instead of multiplenested bearing rings. While shown as including only two nested bearingrings, the bearing assemblies disclosed herein are not limited toincluding only two nested bearing rings, and may include other numbersof multiple nested bearing rings, such as three or more nested bearingrings. Without being bound by theory, it is believed that more nestedbearing rings within a bearing assembly provide for more reduction insliding speeds in the rotating machine.

In operation of bearing assembly 610, rings 612 and 614 exhibitdifferentials in revolutions per minute, such that ring 612 rotates at alower rate than rings 614. While not shown, one or both of rings 612 and614 may be multi-part, segmented rings. Also shown are outer surface 626and inner surface 618 of outer bearing ring 612, and inner surface 626of inner bearing ring 614.

The bearing assemblies shown in FIGS. 7A and 7B are substantiallyidentical to those shown in FIGS. 6A and 6B, with the exception that thebearing engagement surfaces 722 are arcuate, rather than flat. Witharcuate bearing engagement surfaces 722, the entirety or substantiallythe entirety of bearing engagement surfaces 722 are engageable withouter surface 708 of drive shaft 706. The arcuate surfaces of bearingengagement surfaces 722 may be shaped to mate with the arcuate outersurface 708 of drive shaft 706, such that, as drive shaft 706 rotates,bearing engagement surfaces 722 maintain a constant or substantiallyconstant contact with outer surface 708.

In some embodiments, outer bearing ring 712 of bearing assembly 710 caninclude a material that is elastically compressible under bearing loads.In FIG. 7B, outer bearing ring 712 has a geometry configured to providecompliance to bearing assembly 710. In particular, outer bearing ring712 is machined to have cavity 713, which defines spring 715. Inoperation, under sufficient loads, spring 715 compresses, at leastpartially closing cavity 713. In some embodiments, bearing assembly 710includes a squeeze film damper. In operation, bearing assembly 710 mayreduce the relative sliding speed of engaged surfaces of rotatingmachine 7000, such as by reducing the relative sliding speed betweenPDCs 720 and the engagement surfaces of the rotating machine 7000relative to an otherwise identical bearing assembly that includes only asingle bearing ring instead of multiple nested bearing rings. Whileshown as including only two nested bearing rings, the bearing assembliesdisclosed herein are not limited to including only two nested bearingrings, and may include other numbers of multiple nested bearing rings,such as three or more nested bearing rings. Without being bound bytheory, it is believed that more nested bearing rings within a bearingassembly provide for more reduction in sliding speeds in the rotatingmachine.

In operation of bearing assembly 710, rings 712 and 714 exhibitdifferentials in revolutions per minute, such that ring 712 rotates at alower rate than rings 714. While not shown, one or both of rings 712 and714 may be multi-part, segmented rings.

Tilting Arcuate Bearing Pads

Some embodiments include bearing assemblies that include tilting bearingelements. With references to FIGS. 8A-8D, bearing assembly 810 and driveshaft 806 are shown. Bearing assembly 810 includes bearing housing 800,which may be, form, or be coupled with a portion of a rotating machine,drill string, or other machine. Bearing housing 800 includes outersurface 857 and inner surface 859, with inner surface 859 defining anannulus within which drive shaft 806 is positioned. Bearing housing 800includes a plurality of sockets 855 therein, extending from outersurface 857 to inner surface 859. Within each socket 855 is positioned abearing member 861. Each bearing member 861 includes base 863, whichincludes threads 865 for threaded engagement with corresponding threads853 of housing 800. Each bearing member 861 includes a polycrystallinediamond bearing element 820 having an engagement surface 822. Eachpolycrystalline diamond bearing element 820 is engaged with a base 863via tilt coupling 869. Tilt coupling 869 can be any coupling capable ofattaching polycrystalline diamond bearing element 820 with base 863 andof allowing polycrystalline diamond bearing element 820 to tilt relativeto base. Tilt coupling 869 may be a spherical ball (allowing formisalignment between bearing assembly 810 and shaft 806) or cylindricalpin. In some embodiments, bearing member 861 and/or base 863 thereofincludes a material that is elastically compressible, providingcompliance and damping under load.

Each polycrystalline diamond bearing element 820 is positioned andsecured within a socket 855 such that the engagement surface 822 thereofis engaged with the opposing engagement surface, outer surface 808, ofdrive shaft 806. In operation, drive shaft 806 rotates within theannulus defined by bearing housing 800. As drive shaft 806 rotates,polycrystalline diamond bearing elements 820 have compliance sufficientto enable elements 820 to tilt relative to base 863, such as to maintainengagement between engagement surfaces 822 and outer surface 808 ofdrive shaft 806. The engagement surfaces 822 are shown as arcuate, whichallows to engagement surfaces 822 to maintain full or substantially fullcontact with surface 808 during operation. However, the engagementsurfaces are not limited to be arcuate, and may be flat. The capabilityof polycrystalline diamond bearing element 820 to tilt relative theshaft 806 provides space between engagement surface 822 and outersurface 808 where a fluid film can develop during operations. Thedirection of tilting of the bearing pads disclosed herein is in responseto the direction of rotation.

Tilting and Compliant Bearing Pads

Some embodiments include bearing assemblies that include tilting andcompliant bearing elements. The bearing assemblies show in FIGS. 9A-9Dare substantially identical to those shown in FIGS. 8A-8D, with theexception that the polycrystalline diamond bearing elements 920 aremounted onto springs 932 of the bearing member 961. Within each socket955 is positioned a bearing member 961. Each bearing member 961 includesbase 963, which includes threads 965 for threaded engagement withcorresponding threads 953 of housing 900. Each bearing member 961includes a spring 932 coupled with base 963, and a tilt coupling 969coupled with the spring 932. Each polycrystalline diamond bearingelement 920, having an engagement surface 922, is engaged with a tiltcoupling 969. Tilt coupling 969 can be any coupling capable of attachingpolycrystalline diamond bearing element 920 with spring 932 and ofallowing polycrystalline diamond bearing element 920 to tilt relative tobase 963 along arc 999. Spring 932 allows each polycrystalline diamondbearing element 920 to compress towards base 963, along direction 997.

Each polycrystalline diamond bearing element 920 is positioned andsecured within a socket 955 such that the engagement surface 922 thereofis engaged with the opposing engagement surface, outer surface 908, ofdrive shaft 906. In operation, drive shaft 906 rotates within theannulus defined by bearing housing 900. As drive shaft 906 rotates,polycrystalline diamond bearing elements 920 have compliance sufficientto enable elements 920 to tilt relative to base 963. The engagementsurfaces 922 are shown as arcuate; however, the engagement surfaces arenot limited to be arcuate, and may be flat.

In operation a low speed, such as during start-up and shut-down,engagement surfaces 922 are in direct contact with opposing engagementsurface, outer surface 908, of drive shaft 906. In some applications,after start-up and when rotation speed of drive shaft 906 has increased,a fluid film 942 develops between engagement surfaces 922 and outersurface 908 of drive shaft 906. For example, and without limitation, insome applications, a lubricant, drilling fluid, drilling mud, or anotherfluid occupies space between the drive shaft 906 and outer housing 900.In some such applications, operating conditions are sufficient to causethe fluid pressure of the fluid to overcome the bias of springs 932,such that the fluid film 942 is formed, such that bearing surfaces 922of polycrystalline diamond bearing elements 920 are forced out of directcontact with outer surface 908 of drive shaft 906, along line 997. FIG.9D depicts bearing assembly 910 in an operational state having such afluid film 942. During shut down, as the rotation of drive shaft 906slows down to lower rotation speeds, when the fluid pressure of thefluid no longer overcomes the bias of springs 932, springs 932 onceagain bias bearing surfaces 922 of polycrystalline diamond bearingelements 920 into direct contact with outer surface 908. Springs 932 arenot limited to the particular structure shown, and may be any of thecompliance members disclosed herein, such as a rubber member.

The tilt couplings disclosed herein can be offset, relative to thepolycrystalline diamond surfaces, such that the tilt couplings arepositioned at an expected and/or theoretical center of load on thepolycrystalline diamond surfaces.

FIG. 10 is a simplified schematic similar to FIG. 9A, but showing someof the forces involved in compliance, including stiffness 1089 anddamping 1087, on polycrystalline diamond bearing elements 1020 that areengaged with a drive shaft 1006.

FIG. 11 depicts rotating machine 1100, including rotor 1187 movablypositioned within stator 1185, and including drive shaft 1106 movablypositioned within housing 1101. Rotor 1187 is coupled with drive shaft1106 via transmission 1183. Transmission is positioned withintransmission housing 1181. Drive shaft 1106 is coupled with drill bit1179. In operation, rotor 1187 is driven to rotate, such as via passinga drilling mud through stator 1185. The rotation of rotor 1187 drivesthe rotation of drive shaft 1106 through transmission 1183, and therotation of drive shaft 1106 drives the rotation of drill bit 1179. Theengagement between drive shaft 1106 and housing 1101 is interfaced bytwo bearing assemblies 1110 a and 1110 b. Also, the engagement betweenrotor 1187 and stator 1185 is interfaced by two bearing assemblies 1110c and 1110 d. Each bearing assembly 1110 a-1110 d may be a bearingassembly in accordance with the present disclosure, such as those shownand described with reference to FIGS. 1-10.

Polycrystalline Diamond Bearing Elements

In some embodiments, the polycrystalline diamond bearing elementsdisclosed herein include thermally stable polycrystalline diamond,either supported or unsupported by tungsten carbide, or polycrystallinediamond compact. In certain applications, the polycrystalline diamondbearing elements disclosed herein have increased cobalt contenttransitions layers between the outer polycrystalline diamond surface anda supporting tungsten carbide slug. The polycrystalline diamond bearingelements may be supported by tungsten carbide, or may be unsupported,“standalone” polycrystalline diamond bearing elements that are mounteddirectly to the bearing component. The polycrystalline diamond bearingelements may by non-leached, leached, leached and backfilled, thermallystable, coated via chemical vapor deposition (CVD), or processed invarious ways as known in the art.

In some embodiments, the bearing engagement surfaces of thepolycrystalline diamond bearing elements disclosed herein are planar,convex, or concave. In some embodiments, wherein the bearing engagementsurfaces of the polycrystalline diamond bearing elements are concave,the concave bearing engagement surfaces are oriented with the axis ofthe concavity in line with the circumferential rotation of the driveshaft; thereby, reducing the occurrence of edge contact betweenpolycrystalline diamond bearing element and the drive shaft, andproviding for a substantially linear area contact between thepolycrystalline diamond bearing element and drive shaft, generally withthe deepest portion of the concavity. Engagement between polycrystallinediamond bearing elements and drive shaft may be exclusively orsubstantially interfaced by the bearing engagement surface and thesurface of the drive shaft. In some embodiments, the polycrystallinediamond bearing elements have beveled edges.

The polycrystalline diamond bearing elements may have diameters as smallas 3 mm (about ⅛″) or as large as 75 mm (about 3″), depending on theapplication and the configuration and diameter of the bearing.Typically, the polycrystalline diamond bearing elements have diametersbetween 8 mm (about 5/16″) and 25 mm (about 1″).

Although the polycrystalline diamond bearing elements are most commonlyavailable in cylindrical shapes, it is understood that the technology ofthe application may be practiced with polycrystalline diamond bearingelements that are square, rectangular, oval, any of the shapes describedherein with reference to the Figures, or any other appropriate shapeknown in the art. In some applications, the radial bearings have one ormore convex, contoured polycrystalline diamond bearing elements mountedon a rotor (or stator) in sliding contact with a stator (or rotor).

In some applications, the polycrystalline diamond bearing elements aredeployed in bearing rings. A non-limiting example is a bearing ring offive planar face polycrystalline diamond bearing elements deployed on adistal portion of a stator and another bearing ring of five planar facepolycrystalline diamond bearing elements deployed on a proximal portionof the stator. Thus, high-performance polycrystalline diamond bearingelements assemblies can be deployed to ensure stable operation along thelength of the stator/rotor interface.

The polycrystalline diamond bearing elements may be arranged in anypattern, layout, spacing or staggering within the bearing assembly toprovide the desired support, without concern for the need foroverlapping contact with polycrystalline diamond bearing elementsengagement surfaces on the opposing bearing component. Thepolycrystalline diamond bearing elements disclosed herein are, in someembodiments, not shaped to conform to the opposing engagement surface.The polycrystalline diamond bearing elements disclosed herein are, inother embodiments, shaped to conform to the opposing engagement surface.

One performance criterion is that the polycrystalline diamond bearingelement is configured and positioned in such a way as to preclude anyedge contact with the opposing engagement surface or component. For aplanar faced polycrystalline diamond bearing element placed on thestator, such polycrystalline diamond bearing elements typicallyexperience less than full face contact with the rotor. That is, as therotor rotates against the polycrystalline diamond bearing elements, theengagement surface contact area is less than full face. In some aspects,the polycrystalline diamond bearing elements are subjected to edgeradius treatment. In embodiments that employ planar or concavepolycrystalline diamond bearing elements, edge radius treatment of suchpolycrystalline diamond bearing elements is employed. One purpose ofemploying an edge radius treatment is to reduce or avoid potential forouter edge cutting or scribing at the outer limits of the linearengagement area of a given polycrystalline diamond bearing elements withthe opposing engagement surface (e.g., a curved surface).

In some embodiments, the polycrystalline diamond bearing elements aremounted in one or more bearing rings that are deployed to interfaceengagement between the rotor and stator.

Opposing Engagement Surface

In some aspects, the opposing engaging surface, that is, the bearingsurface that is engaged with the polycrystalline diamond bearingsurface, has carbon applied thereto. In some such aspects, the carbon isapplied to the opposing bearing surface prior to engagement with theengagement surface. For example, the opposing bearing surface may besaturated with carbon. Without being bound by theory, it is believedthat such application of carbon reduces the ability of the diamondsolvent-catalyst in the opposing engagement surface to attract carbonthrough graphitization of the surface of the polycrystalline diamondbearing element. That is, the carbon that is applied to the opposingbearing surface functions as a sacrificial layer of carbon. In addition,the opposing bearing surface may be treated via any of the methodsdisclosed and described in the '758 Application. The opposing bearingsurfaces disclosed herein may be surfaces that contain at least 2 wt. %of diamond solvent-catalyst.

Solid Lubricant Source

In certain applications, a solid lubricant source, for example, agraphite or hexagonal boron nitride stick or inclusion, either energizedor not energized, is in contact with the opposing engagement surface. Inother embodiments, the sliding engagement between engagement surface andopposing engagement surface is non-lubricated.

Drive Shaft with Polycrystalline Diamond Bearing Elements

The bearing assemblies disclosed herein may be used in rotatingmachinery, such as in turbines and components thereof. As used herein,downhole tools and downhole drilling tools may be or include, but arenot limited to, rotary steerable tools, turbines, jars, reamers,agitators, MWD tools, LWD tools, and drilling motors. Drill strings mayinclude a number of segments, including drill piping or tubularsextending from the surface, a mud motor (i.e., a positive displacementprogressive cavity mud powered motor) and a drill bit. The mud motor mayinclude a rotor catch assembly, a power section, a transmission, abearing package (bearing assembly), and a bit drive shaft with a bitconnection. The power section generally includes a stator housingconnected to and part of the drill string, and a rotor. The bearingassemblies disclosed herein may be a portion of a bottom hole assembly(BHA), such as is shown in FIGS. 14A-15B, 16A-16F, 17A-17F, and 18A-19Gof the '335 Application. For example, the bearing assemblies disclosedherein may be conical bearings.

One skilled in the art would understand that the bearing assembliesdisclosed herein are not limited to the particular arrangements of partsshown and described with reference to FIGS. 1-11. One skilled in the artwould understand that the features shown and described with respect toFIGS. 1-11 with respect to bearing assemblies can be combined withand/or applied to the bearings and drilling tools disclosed in the '335Application, the '608 Application, the '617 Application, the '631Application, and the '310 Application.

Applications

The bearing assemblies disclosed herein may font) a portion of a machineor other apparatus or system. In some such aspects, the proximal end ofthe stator or outer housing may be connected to another component, suchas a drill string or motor housing by threaded connection, welding, orother connection means as known in the art. In some aspects, if thebearing assembly is used in a downhole application, the distal end ofthe rotor (drive shaft) may be augmented by a thrust bearing and maycarry a threaded connection for the attachment of a drill bit, or thedistal end of the rotor may be a drill bit directly formed on and/orpositioned on the end of the mandrel of the rotor. The componentconnections are not limited to downhole applications, and can be appliedto other applications, for example wind turbine energy generators,mining, or marine applications. Furthermore, discrete versions of thebearing assemblies described herein may be used in a broad array ofother applications including, but not limited to, heavy equipment,automotive, turbines, transmissions, rail cars, mining, computer harddrives, centrifuges, medical equipment, pumps, and motors.

In certain aspects, the bearing assemblies disclosed herein are suitablefor deployment and use in harsh environments (e.g., downhole). In somesuch aspects, the bearing assemblies are less susceptible to fracturethan bearing assemblies where a polycrystalline diamond engagementsurface engages with another polycrystalline diamond engagement surface.In certain aspects, such harsh environment suitable radial bearingsprovide enhanced service value in comparison with bearing assembliesthat include a polycrystalline diamond engagement surface engaged withanother polycrystalline diamond engagement surface. Furthermore, thebearing assemblies disclosed herein may be capable of being spaced apartat greater distances that the spacings required when using bearingassemblies that include a polycrystalline diamond engagement surfaceengaged with another polycrystalline diamond engagement surface. Incertain applications, the bearing assemblies disclosed herein can act asa rotor catch, such as in downhole applications. In lubricatedenvironments, the bearing assemblies may benefit from the hydrodynamiceffect of the lubricant or fluid film creating a clearance between themoving and stationary elements of the bearing assembly.

In some embodiments, the bearing assemblies disclosed herein providepolycrystalline diamond bearing elements having with compliance withoutuse of tilt pads.

While many of the embodiments included herein show and describe thecompliant polycrystalline diamond bearing elements positioned on abearing ring that is arranged between a rotor and stator, the presentdisclosure is not limited to such embodiments. For example, thecompliant bearings disclosed herein may be positioned on the bearinghousing (stator), on the drive shaft (rotor), on a bearing ringpositioned between the bearing housing and drive shaft, or anycombination thereof. For example, in some embodiments, tilting bearingpads may be provided on the drive shaft, and compliance and dampingfeatures may be provided on the bearing housing. However, without beingbound by theory, it is believed that, due to centripetal forces presentduring operations, that embodiment includes the compliant bearingassemblies on a bearing ring positioned between the bearing housing anddrive shaft.

FIG. 12, an exemplary Stribeck curve, is illustrative of the developmentof fluid films in bearings. In FIG. 12, the engagement between bearingsurfaces 1202 and 1204 are shown under three different bearingscenarios, including boundary lubrication 1206 with the bearing surfaces1202 and 1204 in direct surface contact with one another; mixedlubrication 1208, with some fluid film 1212 developed between portionsof the bearing surfaces 1202 and 1204, but with portions of the bearingsurfaces 1202 and 1204 still in direct surface contact with one another;and full-film (hydrodynamic or elasto-hydrodynamic) lubrication 1210with fluid film 1212 developed between portions of the bearing surfaces1202 and 1204, and with no portion of the bearing surfaces 1202 and 1204in direct surface contact with one another.

EMBODIMENTS

Certain embodiments will now be described.

Embodiment 1

A rotating machine, the rotating machine comprising: a stator; a rotormovably coupled with the stator, the rotor having a first opposingbearing engagement surface that comprises a material that contains from2 to 100 weight percent of a diamond solvent-catalyst, based on a totalweight of the material; and a compliant bearing assembly positionedbetween the rotor and the stator, wherein the compliant bearing assemblyinterfaces engagement between the rotor and the stator, the compliantbearing assembly comprising: a first bearing ring comprising a firstplurality of polycrystalline diamond bearing elements, wherein eachpolycrystalline diamond bearing element has a first bearing engagementsurface that is engaged with the first opposing engagement surface; anda spring coupled with the first bearing ring and positioned on the firstbearing ring such that a distance between the first bearing engagementsurfaces are the first opposing engagement surface is variable.

Embodiment 2

The rotating machine of embodiment 1, wherein the stator has a secondbearing surface defining an annulus, wherein the rotor is positionedwithin the annulus, and wherein the compliant bearing assembly ispositioned within the annulus of the bearing housing.

Embodiment 3

The rotating machine of embodiment 2, wherein the rotor is a drive shaftand the stator is a bearing housing.

Embodiment 4

The rotating machine of embodiment 2 or 3, wherein the compliant bearingassembly comprises a second bearing ring having a second plurality ofpolycrystalline diamond bearing elements coupled thereon and havingsecond engagement surfaces that are engaged with the second opposingbearing surface of the stator, wherein the first bearing ring ispositioned between the second bearing ring and the rotor, wherein thesecond bearing ring is positioned between the first bearing ring and thestator, and wherein the spring is coupled between the first bearing ringand the second bearing ring such that a distance between the firstbearing ring and the second bearing ring is variable.

Embodiment 5

The rotating machine of embodiment 4, wherein the spring has at leasttwo positions, the at least two positions including: a first positionwherein the spring is decompressed and the first engagement surfaces areon direct contact with the first opposing engagement surface, and thesecond engagement surfaces are in direct contact with the secondopposing engagement surface; and a second position wherein the spring iscompressed and a fluid film is present between the first engagementsurfaces and the first opposing engagement surface, and a fluid film ispresent between the second engagement surfaces and the second opposingengagement surface.

Embodiment 6

The rotating machine of embodiment 4 or 5, wherein an outer surface ofthe first bearing ring is shaped to define a series of valleys andpeaks, wherein an inner surface of the second bearing ring is shaped todefine a series of valleys and peaks, and wherein the valleys and peaksof the first bearing ring are meshed with the valleys and peaks of thesecond bearing ring.

Embodiment 7

The rotating machine of embodiment 6, wherein the valleys and peaks ofthe inner and outer bearing rings define gear teeth.

Embodiment 8

The rotating machine of any of embodiments 4 to 7, wherein rotation ofthe rotor transfers torque to the first bearing ring, and whereinrotation of the first bearing ring transfers torque to the secondbearing ring.

Embodiment 9

The rotating machine of any of embodiments 1 to 8, wherein the firstbearing ring comprises a body having cavities therein, the cavitiesdefining an outer bearing section and an inner bearing section, whereinthe cavities are positioned between the outer bearing section and theinner bearing section and define a squeeze film area.

Embodiment 10

The rotating machine of embodiment 9, wherein the cavities furtherdefine the spring within the body of the first bearing ring.

Embodiment 11

The rotating machine of embodiment 9 or 10, further comprisingadditional cavities defining tiltable bearing pads on an inner surfaceof the first bearing ring, wherein the first plurality ofpolycrystalline diamond bearing elements are positioned on the tiltablebearing pads.

Embodiment 12

The rotating machine of embodiment 11, wherein the additional cavitiesdefining the tiltable bearing pads define a fulcrum configured to allowthe tiltable bearing pads to tilt in response to load and surface speed.

Embodiment 13

The rotating machine of any of embodiments 1 to 12, wherein the firstopposing engagement surface comprises iron or an alloy thereof, cobaltor an alloy thereof, nickel or an alloy thereof, ruthenium or an alloythereof, rhodium or an alloy thereof, palladium or an alloy thereof,chromium or an alloy thereof, manganese or an alloy thereof, copper oran alloy thereof, titanium or an alloy thereof, or tantalum or an alloythereof.

Embodiment 14

The rotating machine of any of embodiments 1 to 13, wherein the firstbearing ring is a segmented bearing ring comprising multiple segments.

Embodiment 15

The rotating machine of any of embodiments 1 to 14, wherein the springcomprises a mechanical spring.

Embodiment 16

The rotating machine of any of embodiments 1 15, wherein the springcomprises an elastically compressible material.

Embodiment 17

The rotating machine of embodiment 16, wherein the elasticallycompressible material comprises an elastic polymer.

Embodiment 18

The rotating machine of any of embodiments 1 to 17, wherein the springhas at least two positions, the at least two positions including: afirst position wherein the spring is decompressed and the firstengagement surfaces are in direct contact with the first opposingengagement surface; and a second position wherein the spring iscompressed and a fluid film is present between the first engagementsurfaces and the first opposing engagement surface.

Embodiment 19

A rotating machine, the rotating machine comprising: a stator; a rotormovably coupled with the stator, the rotor having a first opposingbearing engagement surface that comprises a material that contains from2 to 100 weight percent of a diamond solvent-catalyst, based on a totalweight of the material; a bearing assembly positioned between the rotorand the stator, wherein the bearing assembly interfaces engagementbetween the rotor and the stator, the bearing assembly comprising: afirst bearing ring comprising a first plurality of polycrystallinediamond bearing elements on an inner surface thereof, wherein eachpolycrystalline diamond bearing element has a first bearing engagementsurface that is engaged with the first opposing engagement surface; asecond bearing ring comprising a second plurality of polycrystallinediamond bearing elements having second bearing engagement surfaces,wherein the second bearing engagement surfaces are engaged with an outersurface of the first bearing ring; and wherein the first and secondbearing rings are arranged in a nested configuration between the statorand the rotor such that the second bearing ring is positioned betweenthe first bearing ring and the stator and the first bearing ring ispositioned between the second bearing ring and the rotor.

Embodiment 20

The rotating machine of embodiment 19, wherein the bearing is acompliant bearing assembly comprising a spring on an outer surface ofthe second bearing ring, the spring positioned such that a distancebetween the second bearing ring the stator is variable.

Embodiment 21

The rotating machine of embodiment 20, wherein the spring is defined bya cavity within the second bearing ring, the spring comprising a portionof the second bearing ring capable of at least partially opening andclosing the cavity in response to load and surface speed.

Embodiment 22

The rotating machine of any of embodiments 19 to 21, wherein the firstand second bearing engagement surfaces are planar.

Embodiment 23

The rotating machine of any of embodiments 19 to 22, wherein the firstand second bearing engagement surfaces are arcuate.

Embodiment 24

The rotating machine of any of embodiments 19 to 23, wherein rotation ofthe rotor transfers torque to the first bearing ring, wherein rotationof the first bearing ring transfers torque to the second bearing ring,and wherein the first and second bearing rings exhibit different ratesof rotation.

Embodiment 25

A rotating machine, the rotating machine comprising: a bearing housinghaving an outer surface and an inner surface, the inner surface definingan annulus; a rotor movably coupled within the annulus of the bearinghousing, the rotor having an opposing engagement surface that comprisesa material that contains from 2 to 100 weight percent of a diamondsolvent-catalyst, based on a total weight of the material; a pluralityof sockets in the bearing housing; and a plurality of polycrystallinediamond bearing elements coupled with the sockets, wherein eachpolycrystalline diamond bearing element has a bearing engagement surfacethat is engaged with the opposing engagement surface, and wherein thepolycrystalline diamond bearing elements are capable of tilting relativeto the outer surface of the bearing housing.

Embodiment 26

The rotating machine of embodiment 25, wherein each polycrystallinediamond bearing element is coupled with a base within one of the socketsvia a tiltable coupling such that the polycrystalline diamond bearingelements are capable of tilting relative to the bases.

Embodiment 27

The rotating machine of embodiment 26, wherein each base is threadablycoupled with the bearing housing.

Embodiment 28

The rotating machine of any of embodiments 25 to 27, wherein, engagedbetween each polycrystalline diamond bearing element and the bearinghousing, is a spring, such that a distance between the bearingengagement surface of each polycrystalline diamond bearing element andthe opposing engagement surface is variable.

Embodiment 29

The rotating machine of embodiment 28, wherein the spring has at leasttwo positions, the at least two positions including a first positionwherein the spring is decompressed and the bearing engagement surfacesare in direct contact with the opposing engagement surface, and a secondposition wherein the spring is compressed and a fluid film is positionedbetween the bearing engagement surfaces and the opposing engagementsurface.

Embodiment 30

A method of bearing load in a rotating machine, the method comprising:providing a bearing housing comprising a first bearing ring comprising afirst plurality of polycrystalline diamond bearing elements, each havinga first bearing engagement surface, the bearing housing having an outersurface and having an inner surface defining an annulus; providing arotor that is movably coupled with a stator, wherein the rotor has anopposing engagement surface that comprises a material that contains from2 to 100 weight percent of a diamond solvent-catalyst, based on a totalweight of the material; positioning the bearing housing between therotor and the stator to interface engagement between the rotor and thestator, wherein the first bearing engagement surfaces are engaged withthe opposing engagement surface; and providing the polycrystallinediamond bearing elements with compliance such that a distance betweenthe first bearing engagement surfaces and the opposing engagementsurface is variable in response to load and surface speed.

Embodiment 31

The method of embodiment 30, comprising passing a fluid through theannulus of the bearing housing, wherein the compliance provides for atleast two positions of the first polycrystalline diamond bearingelements, including a first position wherein the first bearingengagement surfaces are in direct contact with the opposing engagementsurface, and a second position wherein a fluid film is formed betweenthe first bearing engagement surfaces and the opposing engagementsurface.

Embodiment 32

The method of embodiment 30, comprising bearing radial and thrust loadson the drive shaft with the compliant bearing assembly.

Embodiment 33

The method of any of embodiments 30 to 32, wherein the compliance isprovided by engaging a spring between the first polycrystalline diamondbearing elements and the bearing housing.

Embodiment 34

The method of any of embodiments 30 to 33, wherein the bearing housingcomprises a second bearing ring comprising a second polycrystallinediamond bearing element thereon, each having a second bearing engagementsurface that is engaged with a second opposing engagement surface of thestator.

Embodiment 35

The method of embodiment 34, wherein the compliance is provided bypositioning a spring between the first bearing ring and the secondbearing ring such that a distance between the first and second bearingrings is variable in response to load and surface speed.

Embodiment 36

The method of any of embodiments 30 to 35, wherein providing thecompliance comprises providing cavities within a body of the bearinghousing, the cavities defining an outer bearing section and an innerbearing section, wherein the cavities are positioned between the outerbearing section and the inner bearing section and define a squeeze filmarea, and wherein the cavities define a spring within the body of thebearing housing.

Embodiment 37

The method of embodiment 36, wherein the cavities define tiltablebearing pads in the bearing housing, wherein the first plurality ofpolycrystalline diamond bearing elements are positioned on the tiltablebearing pads, and wherein the cavities define a fulcrum configured toallow the tiltable bearing pads to tilt in response to load and surfacespeed.

Embodiment 38

The method of any of embodiments 30 to 37, wherein providing thecompliance comprises coupling the first plurality of polycrystallinediamond bearing elements with the bearing housing via a couplingconfigured to allow the polycrystalline diamond bearing elements to tiltrelative to the bearing housing, via a spring, or combinations thereof.

Embodiment 39

The method of embodiment 38, wherein the polycrystalline diamond bearingelements are threadably coupled within sockets in the bearing housing.

Embodiment 40

A method of bearing load in a rotating machine, the method comprising:providing a first bearing ring comprising a first plurality ofpolycrystalline diamond bearing elements, each having a first bearingengagement surface; providing a second bearing ring comprising a secondplurality of polycrystalline diamond bearing elements, each having asecond bearing engagement surface; providing a rotor that is movablycoupled with a stator, wherein the rotor has an opposing engagementsurface that comprises a material that contains from 2 to 100 weightpercent of a diamond solvent-catalyst, based on a total weight of thematerial; positioning the first bearing ring between the rotor and thestator, wherein the first bearing engagement surfaces are engaged withthe opposing engagement surface; positioning the second bearing ringbetween the stator and the first bearing ring, wherein the secondbearing engagement surfaces are engaged with an outer surface of thefirst bearing ring, and wherein the first and second bearing rings arearranged in a nested configuration.

Embodiment 41

The method of embodiment 40, further comprising providing a spring on anouter surface of the second bearing ring, the spring positioned suchthat a distance between the second bearing ring the stator is variablein response to load and surface speed.

Embodiment 42

The method of embodiment 40 or 41, wherein rotation of the rotortransfers torque to the first bearing ring, wherein rotation of thefirst bearing ring transfers torque to the second bearing ring, andwherein the first and second bearing rings exhibit different rates ofrotation.

Embodiment 43

A bearing assembly for use in rotating machines, the bearing assemblycomprising: a first bearing ring comprising a first plurality ofpolycrystalline diamond bearing elements on an inner surface thereof,wherein each polycrystalline diamond bearing element has a first bearingengagement surface; and a spring coupled with the first bearing ring andpositioned on the first bearing ring such that a position of the firstbearing engagement surfaces is variable.

Embodiment 44

The bearing assembly of embodiment 43, further comprising a secondbearing ring having a second plurality of polycrystalline diamondbearing elements coupled on an outer surface thereof and having secondengagement surfaces, wherein the spring is coupled between an outersurface of the first bearing ring and an inner surface of the secondbearing ring such that a distance between the first bearing ring and thesecond bearing ring is variable.

Embodiment 45

The bearing assembly of embodiment 43 or 44, wherein the outer surfaceof the first bearing ring is shaped to define a series of valleys andpeaks, wherein the inner surface of the second bearing ring is shaped todefine a series of valleys and peaks, and wherein the valleys and peaksof the first bearing ring are meshed with the valleys and peaks of thesecond bearing ring.

Embodiment 46

The bearing assembly of any of embodiments 43 to 45, wherein the valleysand peaks of the inner and outer bearing rings define gear teeth.

Embodiment 47

The bearing assembly of embodiment 44, wherein the first bearing ringcomprises a body having cavities therein, the cavities defining an outerbearing section and an inner bearing section, wherein the cavities arepositioned between the outer bearing section and the inner bearingsection and define a squeeze film area.

Embodiment 48

The bearing assembly of embodiment 47, wherein the cavities furtherdefine the spring within the body of the first bearing ring.

Embodiment 49

The bearing assembly of embodiment 47, further comprising additionalcavities defining tiltable bearing pads on an inner surface of the firstbearing ring, wherein the first plurality of polycrystalline diamondbearing elements are positioned on the tiltable bearing pads.

Embodiment 50

The bearing assembly of embodiment 49, wherein the additional cavitiesdefining the tiltable bearing pads define a fulcrum configured to allowthe tiltable bearing pads to tilt in response to load and surface speed.

Embodiment 51

The bearing assembly of any of embodiments 43 to 50, wherein the firstbearing ring is a segmented bearing ring comprising multiple segments.

Embodiment 52

The bearing assembly of any of embodiments 43 to 51, wherein the springcomprises a mechanical spring.

Embodiment 53

The bearing assembly of any of embodiments 43 to 52, wherein the springcomprises an elastically compressible material.

Embodiment 54

The bearing assembly of embodiment 53, wherein the elasticallycompressible material comprises an elastic polymer.

Embodiment 55

A bearing assembly for use in rotating machinery, the bearing assemblycomprising: a first bearing ring comprising a first plurality ofpolycrystalline diamond bearing elements on an inner surface thereof; asecond bearing ring comprising a second plurality of polycrystallinediamond bearing elements having second bearing engagement surfaces,wherein the second bearing engagement surfaces are engaged with an outersurface of the first bearing ring; and wherein the first and secondbearing rings are arranged in a nested configuration.

Embodiment 56

The bearing assembly of embodiment 55, wherein the bearing is acompliant bearing assembly comprising a spring on an outer surface ofthe second bearing ring.

Embodiment 57

The bearing assembly of embodiment 56, wherein the spring is defined bya cavity within the second bearing ring, the spring comprising a portionof the second bearing ring capable of at least partially opening andclosing the cavity in response to load and surface speed.

Embodiment 58

The bearing assembly of any of embodiments 55 to 57, wherein the firstand second bearing engagement surfaces are planar.

Embodiment 59

The bearing assembly of any of embodiments 55 to 58, wherein the firstand second bearing engagement surfaces are arcuate.

Embodiment 60

A bearing assembly for use in rotating machines, the bearing assemblycomprising: a bearing housing having an outer surface and an innersurface, the inner surface defining an annulus; a plurality of socketsin the bearing housing; and a plurality of polycrystalline diamondbearing elements coupled with the sockets, wherein each polycrystallinediamond bearing element has a bearing engagement surface, and whereinthe polycrystalline diamond bearing elements are capable of tiltingrelative to the outer surface of the bearing housing.

Embodiment 61

The bearing assembly of embodiment 60, wherein each polycrystallinediamond bearing element is coupled with a base within one of the socketsvia a tiltable coupling such that the polycrystalline diamond bearingelements are capable of tilting relative to the bases.

Embodiment 62

The bearing assembly of embodiment 61, wherein each base is threadablycoupled with the bearing housing.

Embodiment 63

The bearing assembly of any of embodiments 60 to 62, wherein, engagedbetween each polycrystalline diamond bearing element and the bearinghousing, is a spring, such that a position of the bearing engagementsurfaces of each polycrystalline diamond bearing element is variable.

Although the present embodiments and advantages have been described indetail, it should be understood that various changes, substitutions andalterations can be made herein without departing from the spirit andscope of the disclosure. Moreover, the scope of the present applicationis not intended to be limited to the particular embodiments of theprocess, machine, manufacture, composition of matter, means, methods andsteps described in the specification. As one of ordinary skill in theart will readily appreciate from the disclosure, processes, machines,manufacture, compositions of matter, means, methods, or steps, presentlyexisting or later to be developed that perform substantially the samefunction or achieve substantially the same result as the correspondingembodiments described herein may be utilized according to the presentdisclosure. Accordingly, the appended claims are intended to includewithin their scope such processes, machines, manufacture, compositionsof matter, means, methods, or steps.

1. A rotating machine, the rotating machine comprising: a stator; arotor movably coupled with the stator, the rotor having a first opposingbearing engagement surface that comprises a material that contains from2 to 100 weight percent of a diamond solvent-catalyst, based on a totalweight of the material; and a compliant bearing assembly positionedbetween the rotor and the stator, wherein the compliant bearing assemblyinterfaces engagement between the rotor and the stator, the compliantbearing assembly comprising: a first bearing ring comprising a firstplurality of polycrystalline diamond bearing elements, wherein eachpolycrystalline diamond bearing element has a first bearing engagementsurface that is engaged with the first opposing engagement surface; anda spring coupled with the first bearing ring and positioned on the firstbearing ring such that a distance between the first bearing engagementsurfaces and the first opposing engagement surface is variable.
 2. Therotating machine of claim 1, wherein the stator has a second bearingsurface defining an annulus, wherein the rotor is positioned within theannulus, and wherein the compliant bearing assembly is positioned withinthe annulus.
 3. (canceled)
 4. The rotating machine of claim 2, whereinthe compliant bearing assembly comprises a second bearing ring having asecond plurality of polycrystalline diamond bearing elements coupledthereon and having second engagement surfaces that are engaged with thesecond opposing bearing surface of the stator, wherein the first bearingring is positioned between the second bearing ring and the rotor,wherein the second bearing ring is positioned between the first bearingring and the stator, and wherein the spring is coupled between the firstbearing ring and the second bearing ring such that a distance betweenthe first bearing ring and the second bearing ring is variable. 5.(canceled)
 6. The rotating machine of claim 4, wherein an outer surfaceof the first bearing ring is shaped to define a series of valleys andpeaks, wherein an inner surface of the second bearing ring is shaped todefine a series of valleys and peaks, and wherein the valleys and peaksof the first bearing ring are meshed with the valleys and peaks of thesecond bearing ring.
 7. (canceled)
 8. (canceled)
 9. The rotating machineof claim 1, wherein the first bearing ring comprises a body havingcavities therein, the cavities defining an outer bearing section and aninner bearing section, wherein the cavities are positioned between theouter bearing section and the inner bearing section and define a squeezefilm area, and wherein the cavities define the spring within the body ofthe first bearing ring.
 10. (canceled)
 11. (canceled)
 12. (canceled) 13.The rotating machine of claim 1, wherein the first opposing engagementsurface comprises iron or an alloy thereof, cobalt or an alloy thereof,nickel or an alloy thereof, ruthenium or an alloy thereof, rhodium or analloy thereof, palladium or an alloy thereof, chromium or an alloythereof, manganese or an alloy thereof, copper or an alloy thereof,titanium or an alloy thereof, or tantalum or an alloy thereof. 14.(canceled)
 15. (canceled)
 16. (canceled)
 17. (canceled)
 18. The rotatingmachine of claim 1, wherein the spring has at least two positions, theat least two positions including: a first position wherein the spring isdecompressed and the first engagement surfaces are in direct contactwith the first opposing engagement surface; and a second positionwherein the spring is compressed and a fluid film is present between thefirst engagement surfaces and the first opposing engagement surface. 19.A rotating machine, the rotating machine comprising: a stator; a rotormovably coupled with the stator, the rotor having a first opposingbearing engagement surface that comprises a material that contains from2 to 100 weight percent of a diamond solvent-catalyst, based on a totalweight of the material; a bearing assembly positioned between the rotorand the stator, wherein the bearing assembly interfaces engagementbetween the rotor and the stator, the bearing assembly comprising: afirst bearing ring comprising a first plurality of polycrystallinediamond bearing elements on an inner surface thereof, wherein eachpolycrystalline diamond bearing element has a first bearing engagementsurface that is engaged with the first opposing engagement surface; asecond bearing ring comprising a second plurality of polycrystallinediamond bearing elements having second bearing engagement surfaces,wherein the second bearing engagement surfaces are engaged with an outersurface of the first bearing ring; and wherein the first and secondbearing rings are arranged in a nested configuration between the statorand the rotor such that the second bearing ring is positioned betweenthe first bearing ring and the stator and the first bearing ring ispositioned between the second bearing ring and the rotor.
 20. Therotating machine of claim 19, wherein the bearing is a compliant bearingassembly comprising a spring on an outer surface of the second bearingring, the spring positioned such that a distance between the secondbearing ring the stator is variable.
 21. The rotating machine of claim20, wherein the spring is defined by a cavity within the second bearingring, the spring comprising a portion of the second bearing ring capableof at least partially opening and closing the cavity in response to loadand surface speed.
 22. (canceled)
 23. (canceled)
 24. (canceled)
 25. Arotating machine, the rotating machine comprising: a bearing housinghaving an outer surface and an inner surface, the inner surface definingan annulus; a rotor movably coupled within the annulus of the bearinghousing, the rotor having an opposing engagement surface that comprisesa material that contains from 2 to 100 weight percent of a diamondsolvent-catalyst, based on a total weight of the material; a pluralityof sockets in the bearing housing; and a plurality of polycrystallinediamond bearing elements coupled with the sockets, wherein eachpolycrystalline diamond bearing element has a bearing engagement surfacethat is engaged with the opposing engagement surface, and wherein thepolycrystalline diamond bearing elements are capable of tilting relativeto the outer surface of the bearing housing.
 26. (canceled) 27.(canceled)
 28. The rotating machine of claim 25, wherein, engagedbetween each polycrystalline diamond bearing element and the bearinghousing, is a spring, such that a distance between the bearingengagement surface of each polycrystalline diamond bearing element andthe opposing engagement surface is variable.
 29. (canceled)
 30. A methodof bearing load in a rotating machine, the method comprising: providinga bearing housing comprising a first bearing ring comprising a firstplurality of polycrystalline diamond bearing elements, each having afirst bearing engagement surface, the bearing housing having an outersurface and having an inner surface defining an annulus; providing arotor that is movably coupled with a stator, wherein the rotor has anopposing engagement surface that comprises a material that contains from2 to 100 weight percent of a diamond solvent-catalyst, based on a totalweight of the material; positioning the bearing housing between therotor and the stator to interface engagement between the rotor and thestator, wherein the first bearing engagement surfaces are engaged withthe opposing engagement surface; and providing the polycrystallinediamond bearing elements with compliance such that a distance betweenthe first bearing engagement surfaces and the opposing engagementsurface is variable in response to load and surface speed.
 31. Themethod of claim 30, comprising passing a fluid through the annulus ofthe bearing housing, wherein the compliance provides for at least twopositions of the first polycrystalline diamond bearing elements,including a first position wherein the first bearing engagement surfacesare in direct contact with the opposing engagement surface, and a secondposition wherein a fluid film is formed between the first bearingengagement surfaces and the opposing engagement surface.
 32. (canceled)33. The method of claim 30, wherein the compliance is provided byengaging a spring between the first polycrystalline diamond bearingelements and the bearing housing.
 34. The method of claim 30, whereinthe bearing housing comprises a second bearing ring comprising a secondpolycrystalline diamond bearing element thereon, each having a secondbearing engagement surface that is engaged with a second opposingengagement surface of the stator.
 35. The method of claim 34, whereinthe compliance is provided by positioning a spring between the firstbearing ring and the second bearing ring such that a distance betweenthe first and second bearing rings is variable in response to load andsurface speed.
 36. The method of claim 30, wherein providing thecompliance comprises providing cavities within a body of the bearinghousing, the cavities defining an outer bearing section and an innerbearing section, wherein the cavities are positioned between the outerbearing section and the inner bearing section and define a squeeze filmarea, and wherein the cavities define a spring within the body of thebearing housing.
 37. (canceled)
 38. The method of claim 30, whereinproviding the compliance comprises coupling the first plurality ofpolycrystalline diamond bearing elements with the bearing housing via acoupling configured to allow the polycrystalline diamond bearingelements to tilt relative to the bearing housing, via a spring, orcombinations thereof.
 39. (canceled)
 40. A method of bearing load in arotating machine, the method comprising: providing a first bearing ringcomprising a first plurality of polycrystalline diamond bearingelements, each having a first bearing engagement surface; providing asecond bearing ring comprising a second plurality of polycrystallinediamond bearing elements, each having a second bearing engagementsurface; providing a rotor that is movably coupled with a stator,wherein the rotor has an opposing engagement surface that comprises amaterial that contains from 2 to 100 weight percent of a diamondsolvent-catalyst, based on a total weight of the material; positioningthe first bearing ring between the rotor and the stator, wherein thefirst bearing engagement surfaces are engaged with the opposingengagement surface; positioning the second bearing ring between thestator and the first bearing ring, wherein the second bearing engagementsurfaces are engaged with an outer surface of the first bearing ring,and wherein the first and second bearing rings are arranged in a nestedconfiguration.
 41. The method of claim 40, further comprising providinga spring on an outer surface of the second bearing ring, the springpositioned such that a distance between the second bearing ring thestator is variable in response to load and surface speed.
 42. The methodof claim 40, wherein rotation of the rotor transfers torque to the firstbearing ring, wherein rotation of the first bearing ring transferstorque to the second bearing ring, and wherein the first and secondbearing rings exhibit different rates of rotation.
 43. (canceled) 44.(canceled)
 45. (canceled)
 46. (canceled)
 47. (canceled)
 48. (canceled)49. (canceled)
 50. (canceled)
 51. (canceled)
 52. (canceled) 53.(canceled)
 54. (canceled)
 55. (canceled)
 56. (canceled)
 57. (canceled)58. (canceled)
 59. (canceled)
 60. (canceled)
 61. (canceled) 62.(canceled)
 63. (canceled)